University of Arkansas Plant Evaluation Program2010 Plants

2010 Report February 2011

This completes the sixteenth year of the statewide plant evaluation program. The current team of cooperators includes
Dr. Jim Robbins, Dr. Jon Lindstrom and Qingfang Chen.

The three test sites are the Hope Research Center (USDA cold hardiness zone 8), Little
Rock (zone 7a), and the Fayetteville Horticulture Research farm (zone 6b). As much
as possible, the three test sites were prepared in a similar manner. Full sun plants
were grown in row-type beds 3' wide with a 7' grass alley. Plant groups are planted
together (i.e. trees are planted together). Trees are spaced 10' apart, shrubs 6'
apart, and herbaceous perennials 4' apart. The Little Rock site was planted on April
16, 2010; Fayetteville was planted on May 25, 2010; Hope planted on April 21, 2010.
Irrigation at all three sites is by a drip system. Plants were fertilized and mulched
after planting. Post-emergent herbicides were used at all three test sites. No disease
or insect control was implemented during the first year. To maintain a tree-like habit,
trees are pruned following final growth measurements. Pruning consists of removing
the bottom one-third of limbs. SHRUBS are NOT pruned. Final growth measurements were taken at Little Rock on October 1; Fayetteville
on October 10; and Hope on September 28.

CJ = cannot judge due to insufficient information or other reasons 1 = Plant has performed well statewide 2 = Plant has performed well in zones 7a and 8. 3 = Plant performed fair statewide 4 = Plant performed fair zones 7a & 8 5 = Plant not recommended 6 = Plant performed well in 6b, poor in 7a & 8 7 = Plant performed fair in 6b, poor in 7a & 8

Lagerstroemia x'Delta Jazz'

Three-gallon plants were donated by Flowerwood Nursery. There were no plant losses
at the end of the first growing season. Average plant size statewide is 41" tall by
29" wide and a year-end growth index (GI) of 0.504 m3. Flowers are very striking. Medium-pink flowers contrast well against the darker
burgundy foliage.

Lagerstroemia 'Early Bird White

Three-gallon plants were donated by Flowerwood Nursery. There were no plant losses
at the end of the first growing season. Average plant size statewide is 24" tall by
30" wide and a year-end growth index (GI) of 0.288 m3. Flowering on White and Lavender is earlier than Purple.

Lagerstroemia 'Early Bird Purple'

Three-gallon plants were donated by Flowerwood Nursery. There were no plant losses
at the end of the first growing season. Average plant size statewide is 24" tall by
28" wide and a year-end growth index (GI) of 0.232 m3. Flowering was nearly peak by
early/mid June.

Lagerstroemia 'Early Bird Lavender'

Three-gallon plants were donated by Flowerwood Nursery. There were no plant losses
at the end of the first growing season. Average plant size statewide is 19" tall by
24" wide and a year-end growth index (GI) of 0.149 m3. Flowering on White and Lavender is earlier than Purple.

Pieris 'Mountain Snow'

Three-gallon plants were donated by Flowerwood Nursery. Only one plant died in the
first year, and that was at Little Rock. All plants in Fayetteville were dead by the
end of the first growing season. Average plant size at Hope and Little Rock is 13"
tall by 14" wide and a year-end growth index (GI) of 0.034 m3. Plants statewide were clearly showing signs of heat/sun stress by August in our
full sun plots.

Michelia maclurei

One-quart plants were donated by Stephen F. Austin Arboretum. One plant died at both
Hope and Little Rock in 2010. Average plant size statewide is 26" tall by 10" wide
and a year-end growth index (GI) of 0.055 m3.

The Ornamentals team would like to express their sincere appreciation to Dr. David
Creech, Stephen F. Austin Arboretum and Flowerwood Nursery for donating the plants
for this season's trial.